Question

$0.24\, g$ of an organic compound gave $0.22 \,g$ $O_{2}$ on complete combustion. If it contains 1.66% hydrogen, then the percentage of C and O will be

• A. 12.5 and 36.6
• B. 25 and 75
• C. 25 and 36.6
• D. 25 and 80

Answer 1

Answer: (B)

$\%$ of $C=\frac{12}{44}\times\frac{\text{Mass of }CO_{2}}{\text{Mass of substance} }\times100 $
$=\frac{12\times0.22}{44\times0.24}\times100=25 ; C=25$,
$H=1.66$
Total $=26.6=100-26.6=73.4$